Railway-traffic-controlling apparatus



Patented May 4, 1926,

UNITED STATES 'BA-TENT oFFIcyE.

roRaTroN or PnNNsYnvANI, Y

RAILWAY-reuneooNrrooelao, errelwoo- Vsuimtim'u; for application 'serialY my. come?, ljod April 23, 1919. The appiifzat'19p are@ gully as, leali,

' Seial No roseo-- l To all whom t may concern.'

Be it known that I, FRAMNEI. N'IQHQLSQN, a Citizen of the United States, roel-Cling at Philadelphia, in the county of Philadelphia and State of Pennsylvania, l have invented certain new andv useful lmproveinents in Railwayrlrefo-Controlling Apparatus, of which the following is a specification.

invention relates to railway7 '@,lliic con.- trolling systems, and particularly to systems of the 'type wherein alternating currents, are Supplied to the Vtrack rails, and, tlo oars or trains are provided-With governing apparaf tus Wl ich is controlled by such currents in the rails. More particularly my invention relates to traclrway cirCLlts and apparatus for use in systems of the-character set forth.

In one System of the ,typo mentioned, it has been proposed to emuloytlie usual track oircuit current, that is, the current which energizes the track relays, as one of the currents for cont'rolling'the train carried apparatus, and to supply kanother current (which I Will term theulinecurrenf) to the rails of' each track sectionin such manner that it flows in the same direction in the two rails. dien this is done, it Will be seen that when a track section is occupied by a train, it' the line current is of sutlicient magnitude and ot proper phase, and if it is sulfliciently unbalanced in the two track rails in fthe rear of the train it may cause the track relay 'for such section to become energized, thuS Causa false proceed signal in the rear civ the train.

One object of vision ot means for immediately opening the circuit of the line current for :a tra-ck section in the event that suchV current causes encriization of the track relay when the section is occupied, tluis'lll'eventine' a false proceed sie-ual in the rear ot the train.

l will describe two forms of trackuay circuits and apparatusI embodying my invention, and'will then point out the novel tea-v -tures thereof in claims. o

ln the accompanying drawings7 Fig, l is a diagrammatic View showing; one form ot' trackxvay circuits and apparatus ,embodying my invention isvthe prof' my lnyootoil Fia. 2 is o View: Similar t-o Iig. l but showing 7i-.modification of the circuits and. apparatus, illustrated @llore/lo Similar referencecharacters refer to siniif G D iso shown in the drawing. It is understood, however, that a complete ksystem embodying my intention' Will .usually oomprisea plurality of successive sections each 'of which is oaolpoodivlth orporeto simile? to that shown' for section C-lD.

f Iioootofl ,ofljaoont the outrance ood of ,seotion GfD' is', o 'roolfloolo Signal SU of the semaphore typo which' 'sional odiootos stoof7 .cautionA or proceed according as the semaphore is in the horizontal, inclined. or vertical position. A similar signal SLD is provided for the section immediately to the right ,ofSoot-o C--D- The section CD is provided with a track circuit comprising a source of alternating current (transformer and ara-finding` 4 of a polyphase relayH, the source andthe relayV Winding connected across the track rails at theenit and Ientrance'ends of tho Section, roSrootiyoly` Roloy Hl oomprisesthe Windingl, which I iyill terin the trackV Winding, a second or local Winding a rotor 6 responsive to currents displaced in phase in 'the two windings, and two contacts? and 8 operated by the rotor.

The localv Winding 5 is supplied (by means o not shown) with alternating current of the sanieofrcquency as that supplied to the pri-` proceed. or caution position, vpole changer P is iu such position 'as tosupply current et The polarity off the track what I will terni normal polarity to the track rails, in which case the contacts of rclay H are swung to the right as shown; but when signal SD is in the stop position, pole changer P is reversed so that current of reverse polarity is supplied to the track rails, in which case the contacts of relay H are swung to the left. O course, when track section C-'D is occupied by a car or train, the supply ot track circuit current from transformer T to the track winding l of relay H is discontinued, so that this relay becomes 'de-energized andy contacts 7 and 8 move to the vertical position.

Signal SC is provided with a caution circuit and a proceed circuit, which circuits are controlled by contact 7 ot the track relay H and by. the iront point of a contact 10 oi a stick relay E. rlfhe caution circuit 'for signal SC is from one terminal B of a suitable source of' current through front point ot contact 10 of relay E, wires 14 and 18, and the operating mechanism of signal SD, to the other terminal O of the same sourcev of cur* rent. lit will be seen that this circuit is closed only when relay E is energized. The proceed circuit for signal SD is from ternir nal B through the. front point of contact 10,

wires 14 and 15, contact 7 oi: relay H, wirel 17, and mechanism oi" signal SD to terminal O. It will be seen that this circuit is closed only when relay H is energized by track cur- Y rent of normal polarity and relay E is energized.

The stick relay E is provided with a pickup circuit which is controlled by contact 8 of relay H, and by a contact 13 actuated by signal SC and closed only when the signal indicates stop. Thiscircuit is from terminal B of a suitable source orp current, through contact 8, wires 19 and 20, contact 13, wires 21 and 23, and winding of relay E to the other terminal O of the same source or' current. It will be seen that this circuit is closed only when signal SC is in the stop position, and relay H is energized. Relay E is provided with a stick circuit which passes 'from terminal B through contact 8, wires 19 and 16, contact 9, wires 22 and 23, and

winding of relay E to the other terminal O This stick circuit,

o'tthe source oic current. it will be noted, is closed only when Vrelays E and il are both energized.

Although as here shown the circuits 'for signal SC pass from a terminal B oic a source of current to a terminal O, and the circuits ifor relay lil pass from a terminal B ot a source of current to a terminal O', it is understood that the terminals B and B, as well as the terminals O and O are distinguished only to facilitate the matter of tracing` the circuits, and that in actual practice the circuits for the signal and for the relay may, and probably will, include one and the same. source.

lditions .in advance.

The operation of the apparatus, in so 'tar as the control oi signal SG is concerned, is as follows:

When the track section C-D is unoccupied, and signal SD is in the proceed or caution position, relays H and E arc both eneigized, relay H being energized in the normal direction, so that signal SC indicates proceed. lt then a car or train enters section CWD, it causes relay H to become deenergized, thereby opening the stick circuit Yl'or relay E at contact 8, so that relay E opens. The opening et contact 10 of course causes signal SC to move to the stop position. As soon as the entire car or train has passed out of section Cf-D into the section at the right oi point B, track relay H becomes energized in the reverse direction, because signal SD willbe at stop and pole changer l? reversed. Signal SD being at stop and contact 13 closed, the pickeup circuit for relay E is closed. As soon as this relay becomes energized, the stick circuit hereinbetore traced becomes ettectire to hold the relay E in the energized condition as long as track relay H continues to be energized, even though contact 13 is opened by the movement et signal SC to the caution or clear position. The energization of relay E closes the caution circuit for signal SC, so that the signal moves to the caution position. l/Vhen the entire car or train has passed out of the section to the rightv of section C-D and signal SD moves to the caution position, the polarity oit the track circuit current in section C--D becomes normal, whereupon relay H reverses and signal SC moves to the proceed position.

Relay E is preferably slow-releasing in character, in order to avoid de-energization ot' this relay while Contact 8 of relay H is swinging from the left lto the right hand position, due to change of polarity 01:' the track circuit current when pole changer l? reverses.

The trackway apparatus shown herein includes means for causing an alternating line current to iow along the two track rails of the section CD in the same direction, which current is controlled by traiific con- 'lhis current is supplied by a. transformer U. When signals tic and SD are both in the proceed position, as shown in Fig. 1, the, path of the line current is :troni transformer U, through wire 24, contact 25, operated by signal SD, wire 26, to the middle point of an impedance 27, thence through the two track rails 2 and 2*L in multiple to a second impedance 28, from the middle point of which the current flows through wires 29 and 30, contact 12 operated by signal SC, wire 31, iront point of contact 11 of relay E, and wire 32 to transformer U. Contact 12 is closed when signal SD is in the proceed or the caution position butwire 24 is disconnected from wire 26 and is' connected with a wire 35 which leads to the middle point of an impedance 36,; the line current is then supplied to the track rails only between impedances 36 and 28. rlvhe circuit for the line current is provided with a branch around signaloperatcd contact 12, which branch isv from wire 29, through wire 83, and back point of contact 11 of relay E, to wire 32. It will be seen, therefore, that the line circuit is closed when signal SC is in the stop position, provided that-relay E is de-energized.

Before proceeding further, it should vbe pointed out that the trackway apparatus here shown is intended for cooperation with tra-in carried governing apparatus in the following manner: `When the tra-in is on a portion of track which is supplied with track kcircuit current of normal polarity and also with linefcurrent, the governing apparatus permits the train to travel at high speed, Vsuch `as miles per hour. When the track is supplied with line current, and with track circuit current of reverse polarity, the governing apparatus prevents the train from proceeding at more than an intermediate speed, such as 35 miles per hour, butwhen the train enters ay portion of track from which the supply of either track circuit current or line currenthas been discontinued, the governing apparatus pre-vents the train from proceeding at more than a low speed, such as 10 miles per hour. One Vform of governingrapparatus which will cooperate in this manner with the trackway .apparatus lshown herein, `is illustrated and described in Letters r Patent of the vUnited States granted on the 7th day of September, 1920, No. 1,351,991 to Lloyd V. Lewis, for railway traiic controlling systems.

' Assuming now that a car or train has entered section C.-D, it will be remembered that the de-energization of track relay H causes stick relay E to open. The closing of the back contact 11of relay E closes the branch around contact 12 in the circuit for the line current, so that such c ar or train may proceed through the section und-er certain speed restrictions determined bythe position of signal SD.

Assuming now that section C-D is occupied by a car or train, and Signal SC is at stop, it is conceivable that owing yto a difference in the resistances of the two lines of track rails, such as would be occasioned by a broken rail in one of the lines or' track rails behind the train, the line current in the rear of the train may be s uiiciently unbalanced in the two rails to cause relay H to become energized. 'If this occurs, the

closing oll'contact 8 will close the ypick-upv circuit for relay E, because since signal SC is at stop, contact 13 is closed; therefore relay E will become energized. The energization of relay E will open the back point of contact 11, thereby cutting oii.'l the supply of line-current to therails of section Cel). Since the line current is the only sourcel of energy by which relay H was energized, and since this current is now disconnected from the trackrails, relay H will become de-energized, thereby de-energizing relay E. The cle-energization of relay E will re-connect he line current to the track rails through vthe back point of contact 1l, and igt the line current again energizes track relay H, the` operation described above will be repeated.

yShould the intermittent action or relays H` and Ebeot' such a period that suliicient energy is supplied to signal SC to move it away from the stop' position, the pickup 'circuit for relay E will be openedr at Contact 13, and the intermittent action of relays H' and 'E will cease until signal SC has returned to the stop position'and contact 13 again closed. I

It will be 'noted that by thisintermittent action ofrelays H and E, the train or car in section C-D isintermittenly deprived rot line current, and this train or car may be compelled to stop, but it will be protected-in the rear by the signa-l SC at stop. Furthermore, should signal SC Jfail to assume the Stop'position behinda car or train,

Vline current-willl continue to be supplied to the car or train during its progress through v the block.

As soon as the entire car or train passes out .of section-0 1), track circuit4 current is again supplied to winding 4L oi rela-y H so that this relay becomes energized and sov causes relay E to become energized, whereupon signal SC moves to the caution position. y The pick-up circuit for relay E becomes opened yas soon as the signal leaves the stop position, but the stick circuit for this relay has been closed at contact 9, so that relay E continues to be energized. Wvhen the signal SC reaches the caution position, the line circuit for section` C-D vbecomes closed at contact 12.

One important feature of the system kshown in Fig. 1, is that the circuit for the line current is normally closed when signal ergized by unbalanced line current and cause the contacts of the track relay to close before signal SC gets beyond the caution position in its movement from the proceed position toward the stop position. Relays H and E would then both be closed, so that signal SC would be restrained from further downward movement and it would remain at the caution position' or return to the proceed position. The track relay H would then continue to be energized because the line current would continue to ilow through contacts, 11 and 12. rlhe object of my invention would then be defeated. To avoid such a condition, the pick-up circuit for relay E includes contact 13, so thatV when the stick circuit for relay E has once been opened at contact 9 due to the entrance of a car or train upon section C-D, it can not again become closed until signal SC has reached the stop position,` wherein contact 12 is, of course, open and relay E can not become energized without disconnecting the line current from the track rails.

There may be cases, however, wherein the conditions are such that the vprovision oi' contact 13 in the pick-up circuit proves to be unnecessary, and in such cases the arrangement shown in Fig. 2 may be einployed.

Referring now to Fig. 2, the apparatus and circuits shown therein are the same as those shown in Fig. 1, exceptfor the control o relay E. The stick circuit for this relay is omitted, and the contact 18 is omitted from the pick-up circuit. rllhe operation is substantially the same as that of the apparatus shown in Fig. 1, the only difference being that it relay H should become energized by line current before signal SC gets beyond the caution position on its way to the stop position, relay E would become energized at once and would remain energized because the line circuit would then be closed at contact 12 and lat the front point ot contact 11. rlhe signal would therefore remain at caution or would return to the proceed position.

The present application is for the same invention as an earlier application tiled by me on the 23rd day of April, 1919, tjerial No. 292,127, for railway traffic controlling apparatus.

Although have herein shown and described only two forms of trackway apparatus and circuits embodying my invention, it is understood that various changes and modiiications may be made therein within the scope ot the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what l' claim is:

1. In combination, a section of railway track, a track circuit comprising a source ot current and a track relay both oi which are. connected across the rails of said section, a signal for said section controlled by said track relay, a line circuit including the two rails of said section in multiple, said latter circuit having two branches, means for closing or opening' one branch according as said signal indicates proceed or stop, and means for opening or closing the other branch according as said track relay is energized or cle-energized.

2. In? combination, a section ot 'railway track, a track circuit comprising a source of current and a track relay both of which are connected across the rails of said section, an auxiliary relay, a signal Jfor said section controlled by said track relayV and by said auxiliary relay, means for energizing said auxiliary relay when said track relay is energized, a line circuit including the two rails ot' said section in multiple, said'l latter circuit having two branches, means for closing or opening one branch according as said signal indicates proceed or stop, and means for opening or closing the other branch according as said auxiliary relayv is energized or cle-energized.

3. In combination, a section of railway track, a track circuit comprising a source of current and a track relay both of which are connected across the rails ot said section, an auxiliary relay, a signal Jfor said section controlled by said track relay and by said auxiliary relay, a line circuit including the two rails of said section in multiple, said latter circuit having two branches one of which is closed or open according as said signal indicates proceed or stopV and the other of which is closed or open according as said auxiliary relay is cle-energized or energized, and means for energizing said auxiliary relay when t'he signal indicates stop and the track relay is energized.

4t. In combination, a section oit' railway track, a track circuit comprising a source of current and a track relay both of which are connected across the rails of said section, an auxiliary relay, a vsignal for said section controlled by saidptrack relay and by said auxiliary relay, a line circuit including vthe two rails of said section in multiple, said latter circuit having two branches one of which is closed or open according as said signal indicates proceed or stop and the other of which is closed or open according as said auxiliary relay is cle-energized or energized, means for energizing said auxiliary relay when the signal indicates stop and the track relay is energized, and lmeans for subsequently eeping said auxiliary relay energized while the track relay is energized even though the signal changes its indication.

5. In combination, a section of railway track, a track circuit comprising-a source of current and a track relay both of Which are connected across therails of said'section, a signal for Said section controlled by said track relay, means for requiring that the signal make a complete movement to the stop position when the track relay becomes cle-energized even though the track relay again becomes energized before such movement is completed, and a line circuit governed by said meansand by said signal and including thev two rails of the section in multiple. l

In testimony whereof I aix my signature.

FRANK I-I. NICHOLSON. 

